1. Field of the Invention
The present invention is directed to a line adjusting and locking device used on a certain type of lens support system for eyeglasses. More particularly, the present invention is directed to an improved adjusting and line locking device adapted for use on eyeglasses of the type described in U.S. Pat. No. 4,202,609.
2. Brief Description of the Prior Art
Different kinds of frames or mountings for eyeglasses, sunglasses, safety glasses and the like are known in the prior art. Most conventional prior art frames or mountings include temple pieces which are hingedly attached to the transparent members (such as lenses, in case of eyeglasses, having optical refractory power) of the eyeglasses, sunglasses, safety glasses and the like.
U.S. Pat. No. 4,202,609 discloses a mounting or support assembly for eyeglasses, sunglasses, safety glasses and the like (hereinafter collectively referred to as eyeglasses) wherein instead of rigid temple pieces, the transparent members (hereinafter lenses) are attached to the respective earpieces by relatively thin flexible lines. More specifically, each lens of the eyeglasses described in U.S. Pat. No. 4,202,609 is attached to an earpiece by a pair of suspension lines which are spaced apart at their respective point of attachment to the lens, and converge to be attached to the earpiece substantially at the front thereof.
An important feature of the lens support assembly disclosed in said patent is that length of the lines is individually adjustable to precisely fit the mounting or support assembly to the person who wears the eyeglasses. Important advantages of the support assembly disclosed in said patent include its aesthetic appeal, light weight, capability for optimal adjustment to maximize comfort to the wearer, and ability of the support assembly to hold or return the lenses into optimal position relative to the wearer's face and eyes after an inadvertent dislocation.
In order to render the length of each suspension line individually adjustable, U.S. Pat. No. 4,202,609 specifically discloses a line adjusting and locking device which includes a locking plate attached to frontal ends of the earpieces by miniature screws.
An additional specific embodiment of an adjusting and locking device to be used in conjunction with the eyeglasses of the type shown in U.S. Pat. No. 4,202,609 is disclosed in International Application Published Under the Patent Cooperation Treaty on June 25, 1981; International Application No. PCT/US79/01106. The just-noted adjusting device, which substantially comprises a beaded body attached to the flexible lines, is also disclosed in copending United States Patent Application (U.S. application Ser. No. 384,248), and assigned to the same assignee as the present application.
There is still another line adjusting and locking device which, although not disclosed in any patent or patent application known to the present inventors, comprises further background to the present invention. This device includes a plurality of small holes disposed transversely in the frontal cylindrical end of each earpiece. Each of the flexible suspension lines is threaded into several (at least two) of the holes, and a retaining cap is thereafter press-fitted upon the cylindrical end of the earpiece.
Although the above summarized line adjusting and locking devices function well in conjunction with the eyeglasses of the type shown in U.S. Pat. No. 4,202,609, there is still room for improvement in this area of technology. Particularly, there is room for improvement for a line adjusting and locking device for use with the eyeglasses of the type shown in U.S. Pat. No. 4,202,609, which is readily adaptable for mass production, easy to adjust and mount, and yet securely holds the flexible suspension lines attached to the earpieces. The present invention provides this improvement.